The present application relates to a wake-up assisting apparatus and a wake-up assisting method, which are designed to help the user to wake up according to his or her sleep state.
Human's sleep can be classified into several stages according to the degree of brain activity. Each of such stages is called “sleep stage.” A sleep stage in which the body is resting but the brain is acting is referred to as REM (Rapid Eye Movement) sleep. It is distinguished from non-REM sleep (including several sleep stages) in which both the body and the brain are resting. A human is ready to wake up in the REM sleep state but is hard to wake up in the non-REM sleep state in which the brain takes a certain length of time for revival.
For the reason mentioned above, there is a need for a wake-up assisting apparatus which detects whether the user's sleep is REM sleep or non-REM sleep and wakes up the user (by giving stimuli for wake-up) according to the result of detection. Japanese Patent Laid-Open No. 2006-192152 (Paragraph 0018 and FIG. 2, hereinafter referred to as Patent Document 1), for example, discloses “Apparatus for determining sleep state” which detects the user's sleep state by means of a body movement sensor and a pulse sensor in combination.